It isn't any different that any other late-model Toyota. Look at the main wiring harness entrance. It is on the driver's side, above where the clutch pedal would be if it had one. There is an extra double sealed passthrough. From the engine compartment, it looks like a baby bottle nipple. It is only large enough for a pair of #10s, which means you'll have to install fuses after you run the wire. If it were mine, I'd use 4008 RigRunner, and just leave it in place when you get back from the trip.
Just remember, mag mounts aren't safe, and you'd be better off with a trunk lip mount in this instance.